Conventionally, crystal vibration devices employing a crystal unit are widely used in resonators and so forth. For example, a piezoelectric device in which a crystal unit is supported in a cantilever manner on a base substrate is disclosed in below-listed Patent Document 1. The crystal unit is formed using an AT cut crystal vibration element in which a thickness shear vibration is a main vibration. In addition, the crystal unit is fixed to the base substrate using a support mount. The support mount is composed of an epoxy resin or a silicone resin for example.
On the other hand, a piezoelectric device employing a crystal unit is disclosed in below-listed Patent Document 2. In this piezoelectric device, the crystal unit is sealed inside a substrate, a seal ring, a lid composed of a metal and a package. The crystal unit is supported in a cantilever manner on the substrate. The crystal unit is bonded to the substrate using a conductive adhesive. In Patent Document 2, it is described that a dimension of the conductive adhesive in a width direction of the crystal unit is given a specific range.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2011-182155
Patent Document 2: Japanese Unexamined Patent Application Publication No. 2001-77651